Roofing.



C. F. HENNING.

ROOFING.

APPLICATION FILED JUNE 25, 1914.

11,]. 87, 1 45 Patented June 13, 1916.

. trusses for the length of the building is pro-' UNITE STATES AT CHARLES F. HENNING, OF CHICAGO, ILLINOIS,- ASSIGNOR TO THE UNITED STATES GYPSUM COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF NEW JERSEY.

ROOFING.

Specif cation of Letters Patent.

Patented June 13, 1916.

Application filed June 25, 1914. Serial No. 847,173.

To all whom it may concern:

Be it known that I, CHARLEs F. HENNING, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have'invented certain new and useful Improvements in Roofing, of which the following is a specification.

My invention relates in general to fireproof building construction and more especially to fire-proof construction for roofs and similar structures.

Heretofore fire-proof roofs have been constructed of metal, clay tile or concrete. These materials have been unsatisfactory owing to their great weight, high cost of material and erection, and other inherent defects and disadvantages which are overinvention.

One of the objects of my invention is-the.

construction of a fire-proof roof which is light'in-weight, low in cost and which may be easily erected by unskilled labor.

Another object of my invention is a fireproof roof construction of calcined gypsum ('plaster-of-Paris) which is waterproof and to which a composition roofing may be directly applied.

An essential object of my invention is the provisionof a fireproof non-corrodible roof having a low coeflicient of expansion and a low heat conductivity resulting in the prevention of condensation of moisture on the under side of the roof where exposed to the air within theb ilding.

Other objects; andadvantages of my in vention will appear as the same is better understood from the explanation in the following specification taken in connection with the accompahying drawing in which- Figure 1 is a vertical section through a roof constructed according to my invention, and Fig. 2 is a section of a roof d%k taken at right angles to the view inFig. 1 and showing the method of laying the tiles.

On the drawing, 1 indicates generally a roof truss composed of members 2 of steel or other suitable material mounted on the supporting-walls,.one of which is shown at 3. A monitor 5 is shown at theridge of the roof constructed of members 6, as is well known in the art. A sufficient number of vided. .Upon the trusses 1 are secured the purlins consisting preferably of channel irons 7 reinforced with angle irons 8, securely fastened to the upper members of the trusses and extending longitudinally of the sum tiles, which are preferably made in lengths of thirty inches, to rest between the flanges, as shown in Fig. 2. A stiffening rod 10 is shown connecting the purlins. The roof deck is constructed of blocks or tiles composed "of calcined gypsum-with or without an admixture of wood fiber, such as excelsior, and preferably provided with reinforcing metal fabric disposed in the tiles near the bottom thereof below the neutral axis.

The tile 11 is manufactured by mixing calcined gypsum with a small quantity of wood fiber and sufficient water to form a plastic mass. When a uniform mixture has been obtained the material is cast in suitable molds and allowed to harden. The reinforc ng fabric 12 is disposed in the lower portion of the tile durin the processes of manufacture. When the tlles are sufliciently hard to be withdrawn from the molds they are removed and heated in kilns at a low temperature to remove surplus moisture. The dry blocks are then dipped in a waterproofing material such as tar, pitch or asphalt, preferably heated, whereby a waterproof coating is formed on the block extending from one-fourth to one-half inch below thesurface thereof. The waterproofing material increases the hardness and toughens the surface of the tile. It also prevents the tile from absorbing moisture which will tend to decrease its tensile strength. Obviously while I have shown a solid tile it may be made hollow by inserting suitable cores in the molds during the process of manufacture. The tiles are made in standard sizes, referably thirty inches lplngiI by 'twelveincl fes wide by three inches t io 'After the supporting structure, as previously described, has been erected the calcined gypsum tiles are readily placed in po- 110 sition by unskilled labor. Beginning at the angle iron 13, which is secured to the subpurlins and forms a stop for the roofing tiles, the tiles are laid on the T-irons and between the flanges thereof as indicated in Fig. 2 until the roof deck is" complete. It will be noted in Fig. 2 that the flanges 14 of the 'T-irons 9 do not extend to a height equal to the thickness of the tiles, leaving a space 15 between the tiles in the upper surface of the roof deck. These spaces are filled with gyp sum-plaster grout and leveled with the surface of the deck. The grout adheres to the tiles and forms a substantially monolithic roof structure. The roof, owing to the waterproofing material applied to the tiles, is substantially waterproof, but preferably a composition such as tar, pitch, or asphalt is mopped on the finished roof deck to further waterproof the same and a'layer of felt paper 24: impregnated with tar, pitch or asphalt is applied directly thereto. lhe felt paper will adhere readily to the deck without the use of nailing strips or other devices. The roof is completed by fastening the nailing strip 16 by means of bolts to the angle iron 13 and applyingto the nailing strip the gutter 17 and gravel stop 18. At 19 I have indicated the form of flashing which is best adapted for use in my structure.

In the monitor 5 l have shown a window frame 20 having a window 21-mounted therein, a water-table 22 being provided to prevent leakage at this point. The construction of the roof, 23 of the monitor 5.is sub stantiallv the same as that of the main roof structure.

During the construction it may be neces saryto cut and fit tile, but this is easily accomplished owing to the fact that them'aterial is suficiently soft to be easily workable with ordinary tools. Metal roofs are, because of their conductivity, subject to condensation on their under sides resulting in rapid corrosion. Clay tile and concrete roofs are also subject to condensation with its attendant disadvantages and are moreover so heavy as to require strong supporting structures. Wood which approaches g sum as a non-conductor is not fireproof.

' t will be readily understood that l have succeeded in constructing a fire-proof roof which is light in weight and easily erected in large units by unskilled labor at a minimum cost. (Ewing to the non-heat-conducting structed according to my invention property of calcined gypsum, roofs conform a perfect insulating medium between the interior and exterior of buildings and are not subject to sweating, a common fault of clay tile and concrete roofs. Calcined gypsum is not corroded by acid or other fumes usually present where industrial processes are carried out. Hence this material solves the problem of non-corrosive and non-condensing roofs for use industrial plants, such as paper mills and cold-storage warehouses. it will be further seen that I have produced a roof which is readily erectedwithout the use of forms, as is necessary with concrete, and without the "necessity of heavy supporting members, which must be used with clay tile. Furthermore, owing to. the larger sizes and lighter weight of my improved tile a -material saving 'in the supporting structure is made. Roofs of calcined gypsum, owing to the low coefiicient of expansion, show no tendency to bulge, spall or crack under temperature changes when constrained.- Calcinedgypsum tile according to my invention is treated with a waterproofing material and composition roofing may be directly applied thereto and will consequently bond with the roof deck.

The term 1oad-sustaining'in the claim is used in the sense that the blocks form the body of'the roof as distinguished. from a mere coating or lining, the term having acquired this meaning in the car roof and analogous arts.

It will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing any of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

ll claim:

A fire-resisting roof or deck construction comprising a skeleton metallic supporting structure and a load-sustaining body consisting of a plurality of calcined gypsum blocks supported by and spanning the spaces of the skeleton structure with their-inner faces euposed to the air within the building.

GHAli-LES F, HENNTLNG.

' Witnesses:

WM. U. BELT, M. A. Kmart. 

